JP4940905B2 - Joint drive robot and control method thereof - Google Patents

Description

  The present invention relates to a joint-driven robot having a joint and a control method thereof.

  In recent years, a leg for walking is provided, the leg is driven, and a foot portion provided at the lower end of the leg is placed on the floor surface based on predetermined gait data to perform a walking motion. Legged mobile robots have been developed. (For example, Patent Document 1)

  In such a legged mobile robot, first, the foot portion of the leg is brought into contact with the floor surface to form a supporting leg, and then the floor surface is pushed by the back of the foot to raise the entire leg portion (the entire robot). Thus, the next walking motion is performed by driving the legs. The driven leg portion is a free leg, while the other leg portion is a support leg. In this way, a walking motion can be performed by alternately switching the free leg and the support leg.

In order to stably perform such a walking motion, it is necessary to control the position of the center of gravity of the entire robot and drive the leg portion. That is, in the case of a biped walking type legged walking type robot having leg portions on the left and right sides, the moment due to the center of gravity of the entire robot does not act on the ground contact surface of the foot portion of the supporting leg that contacts the floor surface to walk. A point (ZMP = Zero Moment Point) is located.
JP-A-5-305580

  The leg portion of the legged mobile robot shown in Patent Document 1 includes a hip joint, a thigh, a knee joint, a lower leg, an ankle joint, and a foot. Then, the amount of movement of the waist is calculated from the deviation between the target center-of-gravity position of the trunk connected to the legs and the actual center-of-gravity position. And the joint angle to drive is calculated | required from the calculated movement amount of the waist, and it drives.

  Each of the above joints is usually driven by a motor. Therefore, it is necessary to calculate the driving amount in order to drive each joint. The driving amount includes motor torque and angle. Then, the motor is controlled so as to follow the target angle of each joint. As described above, in the arithmetic processing unit of the robot, the driving amount is calculated for each motor of each joint.

  By the way, in a legged mobile robot, a target motion is usually realized by combining a plurality of target postures. When executing the target motion of performing stable walking, as the target posture, for example, (1) “follow each predetermined joint target angle” (2) “make the foot follow the floor” (3) “Invert the body” (4) “Absorb the landing impact”, etc.

  In order to achieve the above target postures (1) to (4) at the same time, a control amount is calculated for each target posture. That is, the arithmetic processing unit of the robot has a plurality of control amount calculation units for calculating the control amount corresponding to each target posture. In the above case, four control amount calculation units are provided corresponding to the target postures (1) to (4). Each control amount calculation unit calculates a control amount corresponding to the target posture by executing a predetermined program. Furthermore, the arithmetic processing unit of the robot combines a plurality of control amounts in order to obtain the drive amount of one joint.

  However, it is necessary to combine a large number of target postures so as to achieve more complex movements. Therefore, even if the control amount calculation units are individually optimized and designed according to each target posture, there is a possibility that the robot may move unexpectedly due to interaction as a result of combining them through the combining unit. Here, the unexpected movement is: (a) “does not follow a predetermined target joint angle” (b) “foot does not follow the floor shape” (c) “torso does not invert” (d ) The target posture such as “cannot absorb landing impact” is not satisfied. That is, there is a problem that one or more of the plurality of target postures cannot be achieved.

  In the prior art, the target posture that cannot be achieved is identified, and the corresponding control amount calculation unit is redesigned to prevent the above-described problem from occurring. However, since the redesigned control amount calculation unit is not optimized for the target posture, there is a problem that controllability is deteriorated. That is, in the program in the control amount calculation unit, it is necessary to lower the gain for calculating the control amount. Thus, the conventional robot has a problem that it is difficult to realize complex control with good controllability.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a joint-driven robot capable of realizing complex control with good controllability, and a control method therefor.

The joint-driven robot according to the first aspect of the present invention is a joint-driven robot having a joint that is driven according to an input driving amount, and each of the plurality of target postures of the joint-driven robot. A plurality of control amount calculation units for calculating one control amount for calculating the drive amount according to the overall posture of the joint-driven robot and the target posture of the joint-driven robot indicating each joint target angle A control amount calculation unit group including: a control unit calculated by each control amount calculation unit of the control amount calculation unit group multiplied by a gain and added, and output as a drive amount of the joint; Limit value for storing a limit value for achieving a plurality of target postures without degrading controllability, set for the control amount calculated by at least one control amount calculation unit of the control amount calculation unit group Setting And a comparison unit that compares the limit value and the control amount, and outputs the control amount to the same value as the limit value when the control amount exceeds the limit value in the comparison unit. When the control amount does not exceed the limit value, the control amount is output as it is. According to such a configuration, since the control amount does not exceed the limit value, it is possible to prevent cancellation due to the interaction between the target postures. Therefore, since an appropriate gain can be set for the control amount, complex control can be executed with good controllability.

A joint-driven robot according to a second aspect of the present invention is a joint-driven robot having a joint that is driven in accordance with a drive amount output from a controller, and a plurality of target postures of the joint-driven robot. Te one control amount for determining the drive amount of each controlled variable calculation unit for each calculated according to the target posture of the joint drive robot showing the overall attitude and the joint target angle of the joint drive type robot A plurality of first control amount calculation unit groups provided; the control amount calculated by each control amount calculation unit of the first control amount calculation unit group is multiplied by a gain and then added ; A first controller that outputs a first drive amount for driving the joint drive robot, and one control amount for obtaining the drive amount for each of a plurality of target postures of the joint drive robot. Goal The second has a control amount calculation unit group, the control amount calculated by the control amount calculating section of each of the second control amount calculating section group control amount calculating section is provided with a plurality of each calculated according to A second controller that multiplies the gain and adds the result to output a second drive amount for driving the joint, a first drive amount from the first controller, and a second drive amount from the second controller. A switching unit that switches a driving amount and outputs one of the first driving amount and the second driving amount; and the first driving amount and the second that are output from the switching unit. Is set for the control amount calculated by a joint drive unit that drives the joint according to one of the drive amounts, and at least one control amount calculation unit of the first control amount calculation unit group. Limit to achieve multiple target postures without degrading controllability. A limit value setting unit that stores a threshold value, and a comparison unit that compares the control amount with the limit value, and when the control amount exceeds the limit value in the first controller, The switching unit outputs the second driving amount to the joint driving unit, and the switching unit sets the first driving amount to the joint when the control amount exceeds the limit value in the second controller. It outputs to a drive part. In such a configuration, when the target posture cannot be satisfied, the control amount exceeds the limit value, so that the controller is switched. Therefore, since the controller can be switched appropriately, complex control can be executed with good controllability.

  A joint-driven robot according to a third aspect of the present invention is the joint-driven robot described above, wherein the first controller and the second controller execute opposite target motions. To do. Thereby, when the limit value is exceeded, it is possible to switch to the controller that executes the contradictory target motion, so that it is possible to switch to the control according to the situation.

A control method for a joint-driven robot according to a fourth aspect of the present invention is a control method for a joint-driven robot having a joint that is driven according to an input drive amount, and includes a plurality of joint-driven robots. step one control quantity, a plurality of calculated according to the target posture of the joint drive robot showing the overall attitude and the joint target angle of the joint drive robot for determining the drive amount of each relative to the target orientation And a limit value for achieving a plurality of target postures without lowering controllability for at least one control amount of the plurality of control amounts, and comparing the control amount with the control amount. If the control amount exceeds the limit value, the control amount is output as the same value as the limit value. If the control amount does not exceed the limit value, the control amount is output as it is, The method comprising the Tsu bets value does not exceed the value to the control amount, is added after multiplying the gain in a plurality of control amounts, including the not exceed the limit value value, and outputting a driving amount of the joint, the It is to be prepared. Thereby, since the control amount does not exceed the limit value, it is possible to prevent cancellation due to the interaction between the target postures. Therefore, since an appropriate gain can be set for the control amount, complex control can be executed with good controllability.

A joint-driven robot according to a fifth aspect of the present invention is provided in a joint-driven robot, and a joint that is driven according to a drive amount output from a controller and a plurality of target postures of the joint-driven robot. Te one control amount for determining the drive amount of each controlled variable calculation unit for each calculated according to the target posture of the joint drive robot showing the overall attitude and the joint target angle of the joint drive type robot A plurality of first control amount calculation unit groups provided; the control amount calculated by each control amount calculation unit of the first control amount calculation unit group is multiplied by a gain and then added ; A first controller that outputs a first driving amount for driving the control unit, and a control amount calculation that calculates one control amount for each of a plurality of target postures of the joint-driven robot. Duplicate A second control amount calculating section group provided adds after it has been multiplied by the gain control amount calculated by the control amount calculating section of each of the second control amount calculating section group, the joint And a second controller that outputs a second drive amount to be driven, and a control method for the joint drive robot that drives the joint according to the first drive amount or the second drive amount. A limit value for achieving a plurality of target postures without degrading controllability, set for one or more control amount calculation units in the first control amount calculation unit group, A step of comparing the control amount, a step of switching from the first controller to the second controller when the control amount exceeds the limit value, and the second output from the second controller. Depending on the driving amount of And driving the one in which comprises a. In such a configuration, when the target posture cannot be satisfied, the control amount exceeds the limit value, so that the controller is switched. Therefore, since the controller can be switched appropriately, complex control can be executed with good controllability.

  A control method for a joint-driven robot according to a sixth aspect of the present invention is the control method described above, wherein the first controller and the second controller execute opposite target motions. It is what. Thereby, when the limit value is exceeded, it is possible to switch to the controller that executes the contradictory target motion, so that it is possible to switch to the control according to the situation.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the articulation type robot which can implement | achieve complicated control with sufficient controllability, and its control method.

  The robot according to the first aspect is a joint-driven robot having a joint that is driven according to the output driving amount. This joint-driven robot has a plurality of control amount calculation units for calculating control amounts for determining the drive amount. Here, the control amount is a value used for calculating the driving amount of the joint, and is, for example, a target torque, a target angle, a target angular velocity, or the like of the joint. That is, the control amount is a value that is a control target in driving the joint. Furthermore, the control amount may be the position or angle of a joint other than the joint. For example, the position and inclination angle of the trunk can be used as the control amount. As the control amount changes, the drive amount also changes. The control amount calculation unit calculates the control amount according to the target posture. That is, a target value for performing control for realizing a target posture with respect to the robot is calculated as a control amount. Here, in robot control, since a plurality of target postures are executed in combination, a plurality of control amounts are calculated. The joint-driven robot combines the control amounts calculated by the plurality of control amount calculation units, and outputs them as joint drive amounts. Here, a limit value is set for at least one control amount. When the control amount exceeds the limit value, the control amount is set to a value that does not exceed the limit value.

Embodiment 1 of the Invention
A legged mobile robot (hereinafter simply referred to as a robot) according to a first embodiment of the present invention will be described below with reference to FIG.
FIG. 1 is a schematic diagram schematically showing the robot 1 as viewed from the front, and shows the robot 1 walking on the floor F. FIG. In FIG. 1, for convenience of explanation, the direction in which the robot 1 travels (front-rear direction) is the x-axis, and the direction perpendicular to the horizontal direction (left-right direction) is the y-axis with respect to the direction in which the robot 1 travels. The direction (vertical direction) extending in the vertical direction from the plane to be performed is defined as the z axis, and a description will be made using a coordinate system composed of these three axes. That is, in FIG. 1, the x-axis indicates the depth direction of the paper surface, the y-axis indicates the left-right direction toward the paper surface, and the z-axis indicates the vertical direction in the paper surface.

  As shown in FIG. 1, the robot 1 includes a head 2, a trunk (torso) 3, a waist 4 coupled to the trunk 3, a right arm 5, a left arm 6 connected to the trunk 3, and a waist 4 is a biped walking robot that includes a leg portion 10 that is fixed to be freely pivotable with respect to 4. Details will be described below.

  The head 2 includes a pair of left and right imaging units (not shown) for visually imaging the environment around the robot 1, and the head 2 is parallel to the trunk 3 in the vertical direction. By rotating around the axis, the surrounding environment is imaged widely. Image data indicating the captured surrounding environment is transmitted to the arithmetic processing unit 130 described later, and is used as information for determining the operation of the robot 1.

  The trunk 3 houses therein an arithmetic processing unit 130 that controls the operation of the robot 1, a battery (not shown) for supplying power to a leg motor and the like. The arithmetic processing unit 130 drives the leg 10 and stores a gait data for moving the robot 1, an arithmetic processing unit for reading out the gait data stored in the storage area, and the leg 10. A motor drive unit for driving the included motor. The configuration of the arithmetic processing unit 130 will be described later. Each of these components operates by being supplied with electric power from a battery (not shown) provided inside the trunk 3.

  The arithmetic processing unit 130 reads out the gait data stored in the storage area and calculates the joint angle of the leg 10 necessary to realize the posture of the robot 1 specified by the read out gait data. . And the signal based on the joint angle computed in this way is transmitted to a motor drive part.

  The motor drive unit specifies the drive amount of each motor for driving the leg based on the signal transmitted from the arithmetic processing unit 130, and outputs the motor drive signal for driving the motor with these drive amounts. Send to motor. As a result, the driving amount at each joint of the leg 10 is changed, and the movement of the robot 1 is controlled.

  The arithmetic processing unit 130 commands the motor to be driven based on the read gait data, and signals from sensors (not shown) such as a gyroscope, an accelerometer, and a rotary encoder incorporated in the robot 1. In response, the drive amount of the motor is adjusted. Thus, the robot 1 can be maintained in a stable state by adjusting the joint angle of the leg 10 according to the external force acting on the robot 1 detected by the sensor, the posture of the robot 1, and the like.

  The right arm 5 and the left arm 6 are pivotally connected to the trunk 3, and perform the same movement as a human arm portion by driving joint portions provided at the elbow portion and the wrist portion. Can do. Further, the hand part connected to the tip of the wrist part has a hand structure for gripping an object (not shown), and by driving a plurality of finger joints incorporated in the hand structure, various kinds of parts are provided. It becomes possible to grip an object having a shape.

  The lumbar part 4 is connected to the trunk 3 so as to rotate, and the driving energy necessary for driving the leg part 10 can be obtained by combining the rotational action of the lumbar part 4 when performing a walking action. Can be reduced.

  A leg 10 (right leg 20 and left leg 30) for bipedal walking is composed of a right leg 20 and a left leg 30. Specifically, as shown in FIG. 2, the right leg 20 includes a right hip joint 21, an upper right thigh 22, a right knee joint 23, a right lower leg 24, a right ankle joint 25, and a right foot 26. A left hip joint 31, a left upper thigh 32, a left knee joint 33, a left lower thigh 34, a left ankle joint 35, and a left foot 36 are provided.

  The right leg 20 and the left leg 30 are each driven to a desired angle by transmitting a driving force from a motor (not shown) via a pulley and a belt (not shown). A desired movement can be made to a leg part.

  In this embodiment, when the leg 10 (the right leg 20 and the left leg 30) lifts the lower leg to the front side around the knee joint, the upper leg and the lower leg are placed rearward like a human leg. It is in an open state (a state where the lower leg rotates around the knee joint on the rear side of the extension line of the upper leg).

  The gait data stored in the storage area is associated with the amount of movement of the leg 10 specified by the signal sent from the operation unit (not shown), and the foot of the leg 10 (right foot 26, left foot). 36), the position of the tip (toe) and the position of the main body of the robot 1 are instructed over time in a coordinate system (for example, an xyz coordinate system) that defines a space in which the robot 1 moves. In addition, about the production | generation of gait data, since the method widely used conventionally can be used, description is abbreviate | omitted.

  Here, the arithmetic processing unit 130 will be described. The arithmetic processing unit 130 includes a CPU (Central Processing Unit) that performs predetermined arithmetic processing, a ROM (Read Only Memory) or RAM (Random Access Memory) that is a storage area, a communication interface, and the like. Control the behavior. For example, the ROM stores a control program for control, various setting data, and the like. Then, the CPU reads the control program stored in the ROM and develops it in the RAM. Then, the program is executed in accordance with the setting data and the output from the sensor or the like. In this way, the arithmetic processing unit 130 controls the robot 1.

  Next, the configuration of the arithmetic processing unit 130 of the robot 1 will be described with reference to FIG. FIG. 2 shows a controller 131 for driving one joint among a plurality of joints. Therefore, the arithmetic processing unit 130 is provided with the controllers 131 shown in FIG. 2 by the number of degrees of freedom of joints.

  The controller 131 includes a control amount calculation unit group 145 including a plurality of control amount calculation units 135 and a synthesis unit 138. Each control amount calculation unit 135 calculates a control amount according to the target posture. Here, since a plurality of target postures are set, a plurality of control amount calculation units 135 are provided. Specifically, n control amount calculation units 135 are provided to realize the target posture 1 to the target posture n. That is, the controller 131 includes a control amount calculation unit group 145 including n (n is an integer of 2 or more) control amount calculation units 135.

  The n control amount calculation units 135 included in the control amount calculation unit group 145 have a one-to-one correspondence with the target postures 1 to n. That is, the first control amount calculation unit 135 of the n control amount calculation units 135 is provided to realize the target posture 1, and the nth control amount calculation unit 135 is the target posture. It is provided to realize n. Here, as the target posture, for example, (1) “follow each predetermined joint target angle” (2) “follow the foot on the floor” (3) “invert the body” (4) “Absorb landing impact”. Of course, other target postures may be used, and the number of target postures only needs to be two or more. For example, the control amount calculation unit 135 stores different control amount calculation programs. Thereby, the target postures 1 to n can be achieved simultaneously. Each control amount calculation unit 135 is individually optimized for each target posture.

  Examples of the control amount include a target torque, a target angle, and a target angular velocity of the joint. Of course, it is sufficient that there is at least one of the target torque, the target angle, and the target angular velocity as the control amount, and a plurality of them may be combined. Furthermore, the control amount may be a position other than the joint, an angle, or the like. For example, the position and inclination angle of the trunk can be used as the control amount. Note that a value necessary for calculating the control amount may be input to the control amount calculation unit 135. For example, values such as position and force measured by a sensor provided in the robot 1 are input as necessary.

  Control amounts 1 to n calculated by the control amount calculation unit group 145 are input to the combining unit 138. The synthesizer 138 synthesizes the control amounts 1 to n to calculate the drive amount. For example, the synthesizing unit 138 applies a gain to each of the control amounts 1 to n, and calculates the sum as a drive amount. Then, the combining unit 138 outputs the drive amount obtained by combining the control amounts 1 to n to the motor 141 as a drive signal. A motor 141 that is a joint drive unit that drives the joint is driven according to the drive amount from the synthesis unit 138. For example, when the torque of the motor 141 is used as the drive amount, the motor 141 is rotationally driven with a torque corresponding to the drive amount. Here, since the controller 131 corresponds to one motor 141, one drive amount is output from the controller 131.

  By the way, in conventional robot control, even if the control amount calculation unit 135 is individually optimized for each target posture, the robot may move unexpectedly. This is because, as a result of synthesizing a plurality of control amounts by the synthesizing unit 138, the effects are offset by mutual interaction. The unexpected movement refers to a state in which a plurality of target postures among the above (1) to (4) are not satisfied at the same time. That is, (a) “does not follow a predetermined target joint angle” (b) “foot does not follow the floor shape” (c) “body does not invert” (d) “cannot absorb landing impact A plurality of target unachieved states occur at the same time. Specifically, the foot does not follow the floor shape and the body cannot be inverted, and the robot moves unexpectedly. In order to prevent such a problem, in the conventional robot control, the gain is lowered to lower the controllability.

  In the robot control according to the present embodiment, a plurality of target postures are achieved without lowering controllability by performing the following control. The robot control according to the present embodiment will be described below with reference to FIG. FIG. 3 is a block diagram showing control in the synthesis unit.

  As shown in FIG. 3, the combining unit 138 is provided with a limit value setting unit 136 that sets a limit value for the control amount. Further, the combining unit 138 is provided with a comparison unit 137 that compares the limit value set by the limit value setting unit 136 with the control amount. When the control amount exceeds the limit value, the comparison unit 137 changes the control amount to a value that does not exceed the limit value. Specifically, the comparison unit 137 outputs the control amount with the same value as the limit value. If the control amount does not exceed the limit value, the comparison unit 137 outputs the control amount as it is. As a result, the control amount does not exceed the limit value. Here, limit values are set only for the control amount 1 and the control amount n, but it is also possible to set limit values for other control amounts. Furthermore, the limit value should just be set with respect to one or more control amount.

  These control amounts are input to the conversion unit 139. Here, even when the control amount calculation unit 135 calculates a control amount that exceeds the limit value, the control amount is input to the conversion unit 139 as a value that does not exceed the limit value. The conversion unit 139 converts the control amount into a different control amount. For example, the conversion unit 139 converts the target joint angle into the target torque of the joint. Specifically, an optimized gain is set in each conversion unit 139. Then, the conversion control amount is calculated by multiplying the gain by the control amount. The control amount converted by the conversion unit 139 is set as a conversion control amount. Here, even if the control amount exceeding the limit value is calculated, the control amount is changed by the comparison unit 137 to a value that does not exceed the limit value. Therefore, the conversion unit 139 converts a value that does not exceed the limit value into a conversion control amount.

  The synthesizer 138 synthesizes the conversion control amount. Specifically, the drive amount is calculated by adding the conversion control amounts 1 to n. This drive amount is output from the synthesis unit 138 to the motor 141. Therefore, the motor 141 is driven according to the drive amount. For example, when the conversion control amount is the target torque, the synthesizing unit 138 takes the sum of all the conversion control amounts 1 to n to obtain the final target torque. Thereby, the motor 141 is driven with the target torque. Thus, the drive amount is calculated based on the control amount that does not exceed the limit value.

  As described above, the limit value is set to at least one of the control amounts output from the control amount calculation unit group 145. When the control amount exceeds the limit value, the control amount is set as the limit value. Therefore, the drive amount is calculated based on a value that does not exceed the limit value. Thereby, cancellation by the interaction of each target posture can be prevented. Therefore, the gain with respect to each control amount can be increased, and a decrease in controllability can be prevented. That is, since each control amount calculation unit 135 can be optimally designed, complex control can be performed with good controllability. Furthermore, the controller can be easily designed.

  In the above description, the limit value is set for the control amount, but the limit value may be set for the conversion control amount. For example, when the control amount is the target joint angle and the conversion control amount is the target torque, the limit value can be set not only for the control amount that is the target joint angle but also for the conversion control amount that is the target torque. . Furthermore, the limit value can be set not only for the direct control amount for one joint, but also for the overall control amount (global FB amount) for a plurality of joints. Examples of the total control amount include the waist position, the center of gravity position, the trunk inclination angle, and the leg length of the robot 1. A limit value may be set for the overall control amount used to calculate the drive amounts of the plurality of joints. The joint driven by the motor 141 is not limited to the joint of the leg 10 and may be a joint of another part. That is, operations other than walking motions may be controlled. Thus, controllability can be enhanced even when complex control is performed on a joint-driven robot that drives a joint by a motor.

Embodiment 2 of the Invention
Robot control according to the present embodiment will be described with reference to FIG. FIG. 4 is a block diagram showing the configuration of the arithmetic processing unit of the robot according to the present embodiment. Note that the overall configuration of the robot 1 according to the present embodiment and the basic configuration of the arithmetic processing unit 130 are the same as those in the first embodiment, and thus description thereof is omitted. That is, the basic walking motion is the same as that of the robot 1 according to the first embodiment.

  In the present embodiment, two controllers 131 are provided for one joint. As shown in FIG. 4, one of the two controllers is a first controller 131a, and the other is a second controller 131b. As in the first embodiment, the first controller 131a and the second controller 131b are provided with a combining unit 138 and a plurality of control amount calculation units 135. The combining unit 138 provided in the first controller 131a is referred to as a first combining unit 138a, and the combining unit 138 provided in the second controller 131b is referred to as a second combining unit 138b. The control amount calculation unit 135 provided in the first controller 131a is referred to as a first control amount calculation unit 135a, and the control amount calculation unit 135 provided in the second controller 131b is used as a second control amount calculation. The portion 135b.

  Limit values for control amounts are set in the first combining unit 138a and the second combining unit 138b, respectively. The limit value is set for one or more control amounts. The configuration of the first controller 131a and the second controller 131b is the same as that of the controller 131 described in Embodiment 1, and thus detailed description thereof is omitted.

  The first controller 131a and the second controller 131b are designed to realize different target motions. That is, the first controller 131a and the second controller 131b store a control program for executing a target fate that is not established at the same time. Examples of target exercises are: A “Exercise to walk in a direction determined by a predetermined speed and stride”, B “Next movement according to the current state (without being limited to a predetermined motion) Examples include “exercise that determines a landing position and landing at the landing position”, “C” exercise that interrupts walking and executes danger avoidance exercise according to the current state ”, and the like.

  The above target movements A, B, and C are contradictory and are not realized at the same time. For example, it is assumed that the first controller 131a executes the target motion A and the second controller 131b executes the target motion C. The target motion A executed by the first controller 131a and the target motion C executed by the second controller 131b are contradictory and cannot be realized at the same time. Specifically, the second controller 131b performs an exercise of interrupting walking and executing a danger avoidance exercise according to the current state. In the danger avoidance exercise of the target motion C, the landing is made at a position different from the walking landing position by the target motion A of the first controller 131a. That is, in the second controller 131b, the next landing position is determined according to the current state quantity measured by the sensor or the like in order to perform the danger avoidance exercise without being limited to the predetermined movement. Therefore, the target motion C lands at a position different from the landing position of the target motion A in “a motion that walks in a direction determined by a predetermined speed and stride”. In this case, the driving amounts calculated by the first controller 131a and the second controller 131b should be different values.

  Therefore, in the present embodiment, the arithmetic processing unit 130 is provided with a switching unit 148 that switches between the first controller 131a and the second controller 131b. The switching unit 148 switches the target motion between the first controller 131a and the second controller 131b. That is, assuming that the driving amount from the first controller 131a is the first driving amount and the driving amount from the second controller 131b is the second driving amount, the switching unit 148 has the first driving amount and the first driving amount. Only one of the two driving amounts is output to the motor 141.

  Here, the switching unit 148 switches between the first controller 131a and the second controller 131b when the control amount exceeds the limit value. That is, the switching of the control by the switching unit 148 is performed based on the switching signal 147 from the comparison unit 137. Here, the synthesis unit provided in the first controller 131a is referred to as a first synthesis unit 138a, and the synthesis unit provided in the second controller 131b is referred to as a second synthesis unit 138b. Further, the comparison unit 137 provided in the first combination unit 138a is referred to as a first comparison unit 137a, and the comparison unit 137 provided in the second combination unit 138b is referred to as a second comparison unit 137b.

  The first comparison unit 137a compares the control amount with the limit value set in the limit value setting unit. Then, the first comparison unit 137a outputs a switching signal 147a when the control amount exceeds the limit value. When the switching signal 147a is input, the switching unit 148 switches from the first controller 131a to the second controller 131b. That is, the drive amount output to the motor 141 is switched from the first drive amount to the second drive amount.

  The second comparison unit 137b compares the control amount with the limit value set in the limit value setting unit. Then, the second comparison unit 137b outputs a switching signal 147b when the control amount exceeds the limit value. When the switching signal 147b is input, the switching unit 148 switches from the second controller 131b to the first controller 131a. That is, the drive amount output to the motor 141 is switched from the second drive amount to the first drive amount.

  As described above, the switching unit 148 switches between the first drive amount and the second drive amount in accordance with the switch signal 147. In other words, when the switching signal 147a is input, the switching unit 148 switches and outputs the first driving amount to the second driving amount, and when the switching signal 147b is input, the switching unit 148 outputs the first driving amount from the second driving amount. The drive amount is switched to and output. In other words, when the control amount exceeds the limit value in the first controller 131a, the switching unit 148 outputs the first drive amount to the motor. On the other hand, when the control amount exceeds the limit value in the second controller 131b, the switching unit 148 outputs the second drive amount to the motor. Accordingly, the motor 141 is driven according to the drive amount from the controller 131 that does not exceed the limit value.

  Here, a case where the first controller 131a executes the target motion A and the second controller 131b executes the target motion C will be described. In this case, the arithmetic processing unit 130 normally executes the exercise target A. That is, a predetermined walking motion is executed using the drive amount from the first controller 131a. Accordingly, in a normal time, the switching unit 148 outputs the first drive amount to the motor 141. As long as no disturbance is applied, the control amount does not exceed the set limit value, so the first drive amount continues to be output as it is. Here, the first controller 131a that executes the target motion A has the target postures (1) to (4). That is, (1) “follow each predetermined joint target angle” (2) “follow the foot on the floor” (3) “invert the trunk” (4) “absorb the landing impact The control amount is calculated so as to achieve the target posture of “Yes”. Therefore, during the execution of the target motion A, it is possible to perform a walking motion that follows each predetermined joint target angle. Further, during the walking motion, the foot of the support leg follows the floor surface, and the walking motion is performed with the trunk upside down. And at the time of landing, the landing impact is absorbed.

  However, for example, when a disturbance is applied during the execution of the target motion A, the control amount becomes a value greatly different from the normal time. That is, since the robot 1 is in an unexpected state, the state quantities are greatly different. Therefore, in order to execute the target motion A, a control amount exceeding the limit value is calculated. However, in a situation where a specific control amount exceeds a limit value among a plurality of control amounts 1 to n, if the combining process is performed by the first combining unit 138a, it becomes impossible to satisfy all target postures. . That is, when the control amount exceeds the limit value, the comparison unit 137a changes the control amount to the limit value. Accordingly, the drive amount is obtained based on the control amount within the limit value, not the control amount actually calculated by the control amount calculation unit 135. In this case, the target posture corresponding to the control amount exceeding the limit value cannot be achieved. For example, the foot follows the floor surface F, but the torso cannot be inverted. This makes it impossible to execute the target motion A “walking in a direction determined by a predetermined speed and stride” while achieving all target postures.

  Therefore, in the present embodiment, the controller 131 is switched by the switching signal 147 from the comparison unit 137 as described above. That is, when the comparison unit 137 provided in the synthesis unit 138 determines that the control amount exceeds the limit value, the switching signal 147 for switching to another controller is output. As a result, the drive amount of the controller 131 having the comparison unit 137 whose control amount exceeds the limit value is not output to the motor 141, and the drive amount from other controllers is output to the motor 141.

  If a disturbance occurs during the execution of the target motion A “walking in a direction determined by a predetermined speed and stride”, it is necessary to take a danger avoidance exercise. Here, since the control amount exceeds the limit value when a disturbance occurs, the control is switched from the first controller 131a to the control by the second controller 131b. In other words, when the control amount exceeds the limit value in the comparison result in the comparison unit 137a, it is determined that the current walking motion cannot be continued and it is necessary to take a danger avoidance exercise. Then, the target motion A by the first controller 131a is switched to the target motion C by the second controller 131b.

  Thus, in the present embodiment, a plurality of controllers are switched according to the comparison result between the control amount and the limit value. Thereby, the complicated judgment of switching the plurality of controllers 131 can be easily performed. That is, when the control amount exceeds the limit value, it is determined that all the target postures of the controller cannot be achieved. Therefore, the control is switched to control by another controller, and the motor 141 is driven by the drive amount from the switched controller. Thereby, for example, the target motion A can be switched to the execution of the target motion C as described above. Conversely, it may be determined from the comparison result with the limit value set in the second controller 131b that the danger avoidance exercise is not necessary, and the control may be switched from the second controller 131b to the control by the first controller 131a. . Thereby, a normal walking motion can be executed.

  By doing so, it is possible to appropriately determine whether to switch the controller. Furthermore, it is possible to rationally switch the controller. Even when the control amount calculation unit 135 is increased, switching can be easily performed. In addition, since the selection of the state quantity for determining switching and the design and verification of the switching algorithm can be simplified, the controller can be designed easily. Therefore, complicated control can be performed with good controllability. In the above description, an example in which two controllers are switched has been described, but control may be performed so that three or more controllers are switched. Thereby, a suitable target exercise | movement can be performed according to the present state. The joint driven by the motor 141 is not limited to the joint of the leg 10 and may be a joint of another part. Thus, controllability can be enhanced even when complex control is performed on a joint-driven robot that drives a joint by a motor.

1 is an overall schematic diagram schematically showing an entire robot according to the present invention. It is a block diagram which shows the arithmetic processing part provided in the robot which concerns on Embodiment 1 of this invention. It is a block diagram which shows the synthetic | combination part provided in the robot which concerns on Embodiment 1 of this invention. It is a block diagram which shows the synthetic | combination part provided in the robot which concerns on Embodiment 2 of this invention.

Explanation of symbols

1 robot, 2 heads, 3 trunks, 4 hips, 5 right arms, 6 left arms,
10 legs, 20 right leg, 21 right hip joint, 22 upper right thigh, 23 right knee joint,
24 right lower leg, 25 right ankle joint, 26 right foot,
30 Left leg 30, 31 Left hip joint, 32 Left upper leg, 33 Left knee joint, 34 Left lower leg,
35 left ankle joint, 36 left foot,
130 arithmetic processing units, 131 controller, 135 control amount calculation unit,
136 limit value setting unit, 137 comparison unit, 138 synthesis unit, 139 conversion unit,
141 motor, 145 control amount calculation unit group, 147 switching signal, 148 switching unit,

Claims (6)

A joint-driven robot having a joint that is driven according to an input drive amount,
One control amount for calculating the drive amount for each of the plurality of target postures of the joint-driven robot is the total amount of the joint-driven robot and the joint-driven robot indicating each joint target angle . A control amount calculation unit group having a plurality of control amount calculation units each calculating according to the target posture;
A synthesis unit that multiplies the control amount calculated by each control amount calculation unit of the control amount calculation unit group after multiplying the gain, and outputs the resultant as a drive amount of the joint;
Limit for storing limit values set for the control amount calculated by at least one control amount calculation unit of the control amount calculation unit group to achieve a plurality of target postures without degrading controllability A value setting section;
A comparison unit for comparing the limit value and the control amount,
When the control amount exceeds the limit value in the comparison unit, the control amount is output with the same value as the limit value. When the control amount does not exceed the limit value, the control amount is left as it is. A joint-driven robot that outputs. A joint-driven robot having a joint that is driven according to a drive amount output from a controller,
One control amount for obtaining the drive amount for each of the plurality of target postures of the joint-driven robot is the target of the joint-driven robot indicating the overall posture of the joint-driven robot and each joint target angle. A control amount calculated by each control amount calculation unit of the first control amount calculation unit group, which includes a first control amount calculation unit group provided with a plurality of control amount calculation units that calculate each according to the posture. A first controller that outputs a first drive amount for driving the joint;
A plurality of control amount calculation units are provided for calculating one control amount for each of the plurality of target postures of the joint-driven robot according to the target posture of the joint-driven robot. A second control amount calculation unit group, a control amount calculated by each control amount calculation unit of the second control amount calculation unit group is multiplied by a gain and then added to drive the joint; A second controller that outputs a driving amount of
The first drive amount from the first controller and the second drive amount from the second controller are switched, and one drive amount of the first drive amount and the second drive amount is set. A switching unit for outputting,
A joint drive unit that drives the joint according to one drive amount of the first drive amount and the second drive amount output from the switching unit;
Limit values for achieving a plurality of target postures without degrading controllability set for the control amount calculated by at least one control amount calculation unit of the first control amount calculation unit group Limit value setting section to memorize,
A comparison unit for comparing the control amount and the limit value,
In the first controller, when the control amount exceeds the limit value, the switching unit outputs the second drive amount to the joint drive unit, and in the second controller, the control amount is A joint drive robot in which the switching unit outputs the first drive amount to the joint drive unit when a limit value is exceeded.   The joint-driven robot according to claim 2, wherein the first controller and the second controller execute opposite target motions. A method for controlling a joint-driven robot having a joint that is driven according to an input driving amount,
One control amount for obtaining the drive amount for each of the plurality of target postures of the joint-driven robot is the target of the joint-driven robot indicating the overall posture of the joint-driven robot and each joint target angle. A step of calculating a plurality according to the posture;
A limit value for achieving a plurality of target postures without lowering controllability for at least one control amount of the plurality of control amounts is compared with the control amount, and the control amount determines the limit value. When the control amount exceeds the limit value, the control amount is output with the same value as the limit value.When the control amount does not exceed the limit value, the control amount is output as it is, and a value that does not exceed the limit value is output. Making the control amount;
Multiplying a plurality of control amounts including a value not exceeding the limit value and then adding , and outputting as a drive amount of the joint;
A control method for a joint-driven robot. A joint that is provided in the joint-driven robot and that is driven according to the drive amount output from the controller;
One control amount for obtaining the drive amount for each of the plurality of target postures of the joint-driven robot is the target of the joint-driven robot indicating the overall posture of the joint-driven robot and each joint target angle. A control amount calculated by each control amount calculation unit of the first control amount calculation unit group, which includes a first control amount calculation unit group provided with a plurality of control amount calculation units that calculate each according to the posture. A first controller that multiplies the gain by a gain, adds the gain, and outputs the first drive amount for driving the joint;
A second control amount calculation unit group provided with a plurality of control amount calculation units each for calculating one control amount for obtaining the drive amount for each of a plurality of target postures of the joint-driven robot; A second controller for multiplying the control amount calculated by each control amount calculation unit of the second control amount calculation unit group by a gain and then adding the result to output as a second drive amount for driving the joint A control method for a joint-driven robot that drives the joint according to the first drive amount or the second drive amount,
Limit values for achieving a plurality of target postures without degrading controllability, set for one or more control amount calculation units in the first control amount calculation unit group, and the control amount And when the control amount exceeds the limit value, switching from the first controller to the second controller;
Driving the joint by the second drive amount output by the second controller;
A control method for a joint-driven robot.   6. The joint-driven robot control method according to claim 5, wherein the first controller and the second controller execute opposite target motions.